From: Xerox Lin <xerox_...@htc.com>

When rndis data transfer is in progress, some Windows7 Host PC is not
sending the GET_ENCAPSULATED_RESPONSE command for receiving the response
for the previous SEND_ENCAPSULATED_COMMAND processed.

The rndis function driver appends each response for the
SEND_ENCAPSULATED_COMMAND in a queue. As the above process got corrupted,
the Host sends a REMOTE_NDIS_RESET_MSG command to do a soft-reset.
As the rndis response queue is not freed, the previous response is sent
as a part of this REMOTE_NDIS_RESET_MSG's reset response and the Host
block any more Rndis transfers.

Hence free the rndis response queue as a part of this soft-reset so that
the correct response for REMOTE_NDIS_RESET_MSG is sent properly during the
response command.

Signed-off-by: Rajkumar Raghupathy <rag...@codeaurora.org>
Signed-off-by: Xerox Lin <xerox_...@htc.com>
[AmitP: Cherry-picked this patch and folded other relevant
        fixes from Android common kernel android-4.4]
Signed-off-by: Amit Pundir <amit.pun...@linaro.org>
---
v2: Sanitized the name of original author. Dropped his email address from
    the list of reviewers, since it is no longer valid.

v1: Cherry picked this usb tethering fix from AOSP kernel/common/android-4.4
    tree and to make sure it doesn't get overlooked, submiting it for review
    and comment.

 drivers/usb/gadget/function/rndis.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/usb/gadget/function/rndis.c 
b/drivers/usb/gadget/function/rndis.c
index 943c21a..ab6ac1b 100644
--- a/drivers/usb/gadget/function/rndis.c
+++ b/drivers/usb/gadget/function/rndis.c
@@ -680,6 +680,12 @@ static int rndis_reset_response(struct rndis_params 
*params,
 {
        rndis_reset_cmplt_type *resp;
        rndis_resp_t *r;
+       u8 *xbuf;
+       u32 length;
+
+       /* drain the response queue */
+       while ((xbuf = rndis_get_next_response(params, &length)))
+               rndis_free_response(params, xbuf);
 
        r = rndis_add_response(params, sizeof(rndis_reset_cmplt_type));
        if (!r)
-- 
2.7.4

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